JP4967722B2 - Vehicle control apparatus and control method - Google Patents

Description

  The present invention relates to a control device for a vehicle equipped with an automatic transmission, and more particularly, to an automatic transmission that suppresses a delay in a shift time caused by a response delay of hydraulic pressure when a synchronous rotation speed is not reached during a power-on downshift. Regarding control.

  2. Description of the Related Art Conventionally, an automatic transmission that forms a desired gear stage by combining friction engagement elements such as a clutch and a brake is known. In this automatic transmission, shifting is performed according to the accelerator opening (the amount of depression of the accelerator pedal) and the vehicle speed. For example, when the accelerator opening suddenly increases while the vehicle is traveling, a downshift (referred to as a power-on downshift in the following description) or the like is performed.

  For example, Japanese Patent Laying-Open No. 2005-337410 (Patent Document 1) discloses a gear shift shock and engine rotation by applying an engagement hydraulic pressure at an appropriate timing even when the speed of increase of the input rotation speed is different during a power-on downshift. Disclosed is a shift control method for an automatic transmission that prevents blow-up. This shift control method is an automatic transmission that releases a first engagement element during a downshift and engages a second engagement element. When the downshift command is issued in a power-on state, the first engagement element Is controlled so that the input rotation speed approaches the low speed rotation speed, and when the input rotation speed approaches the low speed rotation speed, the engagement hydraulic pressure for shifting completion is output to the second engagement element. The speed change control method is as described above. The shift control method includes a step of obtaining a time change rate of the input rotation speed during the shift, a step of estimating a time until the input rotation speed of the low speed stage is reached from the input rotation speed during the shift and the time change rate, Determining a timing for outputting the engagement hydraulic pressure to the second engagement element so that the estimated time approximates the response time of the engagement hydraulic pressure of the second engagement element; Outputting engagement hydraulic pressure.

According to the speed change control method disclosed in the above publication, the time required to reach the input rotational speed at the low speed stage is estimated from the input rotational speed and the time change rate, and the relationship between the estimated time and the second engagement element is estimated. Since the timing of outputting the engagement hydraulic pressure to the second engagement element is determined so that the response time of the combined hydraulic pressure is approximate, the hydraulic pressure of the second engagement element is reached when the input rotation speed reaches the rotation speed of the low speed stage. Also, the hydraulic pressure in the engaged state can be reached. Therefore, even when the rising speed of the input rotational speed is different, it is possible to prevent a shift shock and an engine rotational speed.
JP 2005-337410 A

  However, this power-on downshift is performed on the premise that the input shaft rotational speed of the automatic transmission increases to a predetermined synchronous rotational speed as the accelerator opening increases and the engine rotational speed increases. Therefore, in a power-on downshift in which hydraulic control during shifting (control of hydraulic pressure supplied to the friction engagement element) is performed according to the input shaft rotation speed of the automatic transmission, the accelerator opening is reduced during shifting. As a result, the input shaft rotation speed of the automatic transmission does not increase to the synchronous rotation speed, so that the shift progress may be delayed.

  In the speed change control method disclosed in the above-mentioned publication, control for forcibly proceeding speed change (hereinafter also referred to as sweep control) is performed by increasing the engagement side hydraulic pressure at a predetermined rate of change. However, when shifting from the initial control to the sweep control, there is a problem that the response of the actual hydraulic pressure is delayed until the hydraulic pressure rises to the piston end pressure with respect to the hydraulic pressure command value. For this reason, it is impossible to avoid a delay in the shift time. In the speed change control method disclosed in the above-mentioned publication, since the problem of the response delay of the actual pressure at the start of the sweep control is not considered at all, this problem cannot be solved.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to suppress a delay of a shift time caused by a response delay of a hydraulic pressure when the synchronous rotational speed is not reached during a power-on downshift. A vehicle control device, a control method, a program for realizing the method by a computer, and a recording medium on which the program is recorded are provided.

  In the vehicle control device according to the first aspect of the present invention, the first friction engagement element in the released state is engaged by the hydraulic pressure supplied based on the command value output to the hydraulic circuit, and the second in the engaged state is engaged. This is a control device for a vehicle equipped with an automatic transmission that forms a shift stage after downshifting by releasing the frictional engagement element. This control device is based on detection means for detecting a physical quantity related to the state of the automatic transmission, and on the state of the automatic transmission after the formation of the shift stage after downshift is started due to an increase in the accelerator opening. Determining means for determining whether or not a condition indicating a delay in shifting is satisfied, and when the condition is satisfied, a command value corresponding to the hydraulic pressure supplied to the first friction engagement element is determined in advance. And a means for outputting the command value so as to decrease stepwise when a predetermined time elapses, and a rate of change determined in advance using the predetermined command value as an initial value. And a means for outputting a command value so as to increase. A vehicle control method according to a fifth invention has the same configuration as the vehicle control device according to the first invention.

  According to the first invention, when the accelerator opening increases, the first friction engagement element is engaged, the second friction engagement element is released, and the power-on downshift is performed. At this time, a condition indicating a delay in the progress of the shift (for example, a condition that the rotation speed of the output shaft of the automatic transmission continues to be lower than a predetermined rotation speed corresponding to the shift stage after the downshift) When is established, the command value increases stepwise. Thereby, when the condition is satisfied, the actual hydraulic pressure of the first friction engagement element can be quickly increased as compared with the case where the command value is increased at a predetermined rate of change. Further, since the pressure is lowered stepwise after a predetermined time has elapsed, the engagement side hydraulic pressure is not excessively applied during the shift, and the occurrence of a shift shock can be suppressed. Further, if the command value is output so as to increase at a predetermined rate of change with a predetermined command value as an initial value after the stepwise change of the command value, the downshift can be gradually advanced. Therefore, it is possible to suppress shift time delay and shift shock. Therefore, it is possible to provide a vehicle control device and a control method that suppress a shift time delay caused by a response delay of hydraulic pressure when the synchronous rotational speed is not reached during a power-on downshift.

  In the vehicle control apparatus according to the second invention, in addition to the configuration of the first invention, the detecting means includes means for detecting the rotational speed of the input shaft of the automatic transmission. The control device includes means for calculating a rotation speed difference between the detected rotation speed and the synchronized rotation speed after the downshift, and if the condition is satisfied, the calculated rotation speed difference is within a predetermined range. Then, it further includes means for outputting the command value so that the first friction engagement element increases until the hydraulic pressure is fully engaged. A vehicle control method according to a sixth invention has the same configuration as the vehicle control device according to the second invention.

  According to the second invention, when the condition is satisfied, the engagement-side hydraulic pressure increases due to a step change in the command value. When the rotational speed difference from the synchronous rotational speed is within a predetermined range, it can be determined that the rotational speed of the input shaft of the automatic transmission has reached the synchronous rotational speed. Therefore, by outputting a command value so as to increase until the hydraulic pressure at which the second frictional engagement element is fully engaged, the shift shock caused by excessive application of hydraulic pressure on the engagement side is suppressed, and the shift is performed. can do.

  In the vehicle control apparatus according to the third aspect of the invention, in addition to the configuration of the first aspect of the invention, the detection means includes means for detecting the rotational speed of the input shaft of the automatic transmission. The control device includes a means for calculating a rotational speed difference between the detected rotational speed and the synchronous rotational speed after the downshift, and the detected rotational speed difference is predetermined when the condition is not satisfied. When the value falls within the range, the command value corresponding to the engagement hydraulic pressure of the first friction engagement element is increased stepwise for a predetermined time, and then the command value is output so as to decrease stepwise. And a means for outputting the command value so as to increase until the hydraulic pressure at which the first friction engagement element is fully engaged is obtained with a predetermined command value as an initial value. A vehicle control method according to a seventh aspect has the same configuration as the vehicle control apparatus according to the third aspect.

  According to the third invention, when the condition is not satisfied, the command value does not change stepwise and does not increase at a predetermined change rate, so that the engagement side hydraulic pressure is relatively low. Become. When the rotational speed difference from the synchronous rotational speed is within a predetermined range, it can be determined that the rotational speed of the input shaft of the automatic transmission has reached the synchronous rotational speed. Therefore, the hydraulic pressure can be increased with good responsiveness by changing the command value stepwise. As a result, the second friction engagement element can be quickly fully engaged, and the shift stage after the downshift can be formed.

  In the vehicle control apparatus according to the fourth invention, in addition to the configuration of any one of the first to third inventions, the detecting means includes means for detecting the rotational speed of the input shaft of the automatic transmission. The condition is that the detected rotational speed of the input shaft is lower than the rotational speed set corresponding to the speed stage after the downshift until a predetermined time has elapsed since the start of the speed stage. The condition is that the state continues. A vehicle control method according to an eighth aspect has the same configuration as the vehicle control apparatus according to the fourth aspect.

  According to the fourth aspect of the present invention, the rotation speed of the detected input shaft is set in accordance with the downshifted speed until a predetermined time elapses after the start of the speed change. If the state lower than the number continues, it can be determined that the progress of the shift is delayed. For this reason, when the condition is satisfied, the command value is increased stepwise, so that the shift time delay can be suppressed while the shift shock and the hydraulic response delay are suppressed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  A vehicle equipped with a control device according to an embodiment of the present invention will be described with reference to FIG. This vehicle is an FF (Front engine Front drive) vehicle. A vehicle other than FF may be used.

  The vehicle includes an engine 1000, an automatic transmission 2000, a planetary gear unit 3000 that forms part of the automatic transmission 2000, a hydraulic circuit 4000 that forms part of the automatic transmission 2000, a differential gear 5000, a drive shaft 6000, Front wheel 7000 and ECU (Electronic Control Unit) 8000 are included. The vehicle control apparatus according to the present invention is implemented by ECU 8000.

  Engine 1000 is an internal combustion engine that burns a mixture of fuel and air injected from an injector (not shown) in a combustion chamber of a cylinder. The piston in the cylinder is pushed down by the combustion, and the crankshaft is rotated.

  Automatic transmission 2000 is connected to engine 1000 via torque converter 3200. Automatic transmission 2000 changes the rotational speed of the crankshaft to a desired rotational speed by forming a desired gear stage.

  The output gear of automatic transmission 2000 is meshed with differential gear 5000. A drive shaft 6000 is connected to the differential gear 5000 by spline fitting or the like. Power is transmitted to the left and right front wheels 7000 via the drive shaft 6000.

  The ECU 8000 includes a vehicle speed sensor 8002, a position switch 8006 of a shift lever 8004, an accelerator opening sensor 8010 of an accelerator pedal 8008, a stroke sensor 8014 of a brake pedal 8012, a throttle opening sensor 8018 of an electronic throttle valve 8016, An engine speed sensor 8020, an input shaft speed sensor 8022, and an output shaft speed sensor 8024 are connected via a harness or the like.

  Vehicle speed sensor 8002 detects the speed of the vehicle from the rotational speed of drive shaft 6000 and transmits a signal representing the detection result to ECU 8000. The position of shift lever 8004 is detected by position switch 8006, and a signal representing the detection result is transmitted to ECU 8000. Corresponding to the position of the shift lever 8004, the gear stage of the automatic transmission 2000 is automatically formed. Further, a manual shift mode in which the driver can select an arbitrary gear position may be selected according to the driver's operation.

  Accelerator opening sensor 8010 detects the opening of accelerator pedal 8008 and transmits a signal representing the detection result to ECU 8000. Stroke sensor 8014 detects the stroke amount of brake pedal 8012 and transmits a signal representing the detection result to ECU 8000.

  The throttle opening sensor 8018 detects the opening of the electronic throttle valve 8016 whose opening is adjusted by the actuator, and transmits a signal indicating the detection result to the ECU 8000. Electronic throttle valve 8016 adjusts the amount of air taken into engine 1000 (output of engine 1000).

  Engine rotation speed sensor 8020 detects the rotation speed of the output shaft (crankshaft) of engine 1000 and transmits a signal representing the detection result to ECU 8000. Input shaft rotational speed sensor 8022 detects input shaft rotational speed (hereinafter also referred to as turbine rotational speed) NT of automatic transmission 2000, and transmits a signal representing the detection result to ECU 8000. Output shaft rotational speed sensor 8024 detects output shaft rotational speed NO of automatic transmission 2000 and transmits a signal representing the detection result to ECU 8000. Since the output shaft of engine 1000 is connected to the input shaft of torque converter 3200 and the output shaft of torque converter 3200 is connected to the input shaft of automatic transmission 2000, the rotational speed of the output shaft of engine 1000 is the torque. The rotational speed is the same as the rotational speed of the input shaft of converter 3200. Further, the input shaft rotation speed of automatic transmission 2000 is the same as the rotation speed of the output shaft of torque converter 3200.

  ECU 8000 is sent from vehicle speed sensor 8002, position switch 8006, accelerator opening sensor 8010, stroke sensor 8014, throttle opening sensor 8018, engine speed sensor 8020, input shaft speed sensor 8022, output shaft speed sensor 8024, and the like. Based on the received signal, a map and a program stored in a ROM (Read Only Memory), the devices are controlled so that the vehicle is in a desired running state.

  In the present embodiment, ECU 8000 shifts from 1st to 6th gears when D (drive) range is selected as the shift range of automatic transmission 2000 when shift lever 8004 is positioned at the D (drive) position. Automatic transmission 2000 is controlled so that one of the gears is formed. The automatic transmission 2000 can transmit the driving force to the front wheels 7000 by forming any one of the first to sixth gears.

  When the shift lever 8004 is in the N (neutral) position, when the N (neutral) range is selected as the shift range of the automatic transmission 2000, the automatic transmission 2000 is controlled so as to be in the neutral state (power transmission cut-off state). Is done.

  With reference to FIG. 2, planetary gear unit 3000 provided in automatic transmission 2000 will be described. Planetary gear unit 3000 is connected to a torque converter 3200 having an input shaft 3100 coupled to a crankshaft. Planetary gear unit 3000 includes first set 3300 of planetary gear mechanisms, second set 3400 of planetary gear mechanisms, output gear 3500, B1 brake 3610, B2 brake 3620 and B3 brake 3630 fixed to gear case 3600, and C1. Clutch 3640 and C2 clutch 3650, and one-way clutch F3660 are included.

  The first set 3300 is a single pinion type planetary gear mechanism. First set 3300 includes sun gear S (UD) 3310, pinion gear 3320, ring gear R (UD) 3330, and carrier C (UD) 3340.

  Sun gear S (UD) 3310 is coupled to output shaft 3210 of torque converter 3200. Pinion gear 3320 is rotatably supported by carrier C (UD) 3340. Pinion gear 3320 is in mesh with sun gear S (UD) 3310 and ring gear R (UD) 3330.

  Ring gear R (UD) 3330 is fixed to gear case 3600 by B3 brake 3630. Carrier C (UD) 3340 is fixed to gear case 3600 by B1 brake 3610.

  The second set 3400 is a Ravigneaux type planetary gear mechanism. The second set 3400 includes a sun gear S (D) 3410, a short pinion gear 3420, a carrier C (1) 3422, a long pinion gear 3430, a carrier C (2) 3432, a sun gear S (S) 3440, and a ring gear R. (1) (R (2)) 3450.

  Sun gear S (D) 3410 is coupled to carrier C (UD) 3340. Short pinion gear 3420 is rotatably supported by carrier C (1) 3422. Short pinion gear 3420 is in mesh with sun gear S (D) 3410 and long pinion gear 3430. Carrier C (1) 3422 is coupled to output gear 3500.

  Long pinion gear 3430 is rotatably supported by carrier C (2) 3432. Long pinion gear 3430 is in mesh with short pinion gear 3420, sun gear S (S) 3440, and ring gear R (1) (R (2)) 3450. Carrier C (2) 3432 is coupled to output gear 3500.

  Sun gear S (S) 3440 is coupled to output shaft 3210 of torque converter 3200 by C1 clutch 3640. Ring gear R (1) (R (2)) 3450 is fixed to gear case 3600 by B2 brake 3620 and connected to output shaft 3210 of torque converter 3200 by C2 clutch 3650. The ring gear R (1) (R (2)) 3450 is connected to the one-way clutch F3660 and cannot rotate when the first gear is driven.

  The one-way clutch F3660 is provided in parallel with the B2 brake 3620. That is, the outer race of the one-way clutch F3660 is fixed to the gear case 3600, and the inner race is connected to the ring gear R (1) (R (2)) 3450 via the rotation shaft.

  The B1 brake 3610, the B2 brake 3620, the B3 brake 3630, the C1 clutch 3640, and the C2 clutch 3650 include an input-side friction member, an output-side friction member, a piston that applies a pressing force to the friction member, and hydraulic pressure to the piston. A friction engagement element including a hydraulic chamber to be applied, wherein the input-side friction member and the output-side friction member are configured by, for example, a multi-plate clutch having a plurality of friction members on the input side and the output side, respectively. Is done.

  FIG. 3 shows an operation table showing the relationship between the respective shift speeds and the operation states of the clutch elements and the brake elements. By operating each brake element and each clutch element in the combination shown in this operation table, a forward speed stage of 1st to 6th speed and a reverse speed stage are formed.

  As shown in FIG. 3, the C1 clutch 3640 is engaged in all of the first to fourth gears. That is, it can be said that the C1 clutch 3640 is an input clutch in the first gear to the fourth gear. C2 clutch 3650 is engaged at the fifth speed and the sixth speed. That is, it can be said that C2 clutch 3650 is an input clutch at the fifth speed and the sixth speed.

  In the present embodiment, the case where the present invention is applied to an automatic transmission having two input clutches will be described. However, the present invention is not particularly limited as long as it is an automatic transmission having two or more input clutches. Absent.

  The main part of the hydraulic circuit 4000 will be described with reference to FIG. The hydraulic circuit 4000 is not limited to the one described below.

  The hydraulic circuit 4000 includes an oil pump 4004, a primary regulator valve 4006, a manual valve 4100, a solenoid modulator valve 4200, an SL1 linear solenoid (hereinafter referred to as SL (1)) 4210, and an SL2 linear solenoid (hereinafter referred to as “the solenoid valve”). 4220, SL3 linear solenoid (hereinafter referred to as SL (3)) 4230, SL4 linear solenoid (hereinafter referred to as SL (4)) 4240, and SLT linear solenoid (hereinafter referred to as SL (2)). , SLT) 4300 and a B2 control valve 4500.

  Oil pump 4004 is connected to the crankshaft of engine 1000. As the crankshaft rotates, the oil pump 4004 is driven to generate hydraulic pressure. The hydraulic pressure generated by the oil pump 4004 is regulated by the primary regulator valve 4006 to generate a line pressure.

  Primary regulator valve 4006 operates using the throttle pressure regulated by SLT 4300 as a pilot pressure. Line pressure is supplied to manual valve 4100 and SL (4) 4240 via line pressure oil passage 4010.

  Manual valve 4100 includes a drain port 4105. From the drain port 4105, the oil pressure in the D range pressure oil passage 4102 and the R range pressure oil passage 4104 is discharged. When the spool of the manual valve 4100 is in the D position, the line pressure oil passage 4010 and the D range pressure oil passage 4102 are communicated, and hydraulic pressure is supplied to the D range pressure oil passage 4102. At this time, the R range pressure oil passage 4104 and the drain port 4105 are communicated, and the R range pressure of the R range pressure oil passage 4104 is discharged from the drain port 4105.

  When the spool of the manual valve 4100 is in the R position, the line pressure oil passage 4010 and the R range pressure oil passage 4104 are communicated, and the oil pressure is supplied to the R range pressure oil passage 4104. At this time, the D-range pressure oil passage 4102 and the drain port 4105 are communicated, and the hydraulic oil in the D-range pressure oil passage 4102 is discharged from the drain port 4105.

  When the spool of the manual valve 4100 is in the N position, both the D range pressure oil passage 4102 and the R range pressure oil passage 4104 are connected to the drain port 4105, and the hydraulic oil and R in the D range pressure oil passage 4102 are communicated. The hydraulic oil in the range pressure oil passage 4104 is discharged from the drain port 4105.

  The oil pressure supplied to the D-range pressure oil passage 4102 passes through the SL (1) 4210, SL (2) 4220, SL (3) 4230, and the oil passage 4106, and finally the B1 brake 3610 and the B2 brake. 3620, C1 clutch 3640 and C2 clutch 3650. The hydraulic pressure supplied to the R range pressure oil passage 4104 is finally supplied to the B2 brake 3620.

  The solenoid modulator valve 4200 adjusts the hydraulic pressure (solenoid modulator pressure) supplied to the SLT 4300 to a constant pressure using the line pressure as the original pressure.

  SL (1) 4210 regulates the hydraulic pressure supplied to the C1 clutch 3640. SL (2) 4220 regulates the hydraulic pressure supplied to C2 clutch 3650. SL (3) 4230 regulates the hydraulic pressure supplied to the B1 brake 3610. SL (4) 4240 regulates the hydraulic pressure supplied to the B3 brake 3630. SL (1) 4210, SL (2) 4220, SL (3) 4230, SL (4) 4240, and SLT 4300 are controlled by a control signal transmitted from ECU 8000.

  The SLT 4300 adjusts the solenoid modulator pressure in accordance with a control signal from the ECU 8000 based on the accelerator opening detected by the accelerator opening sensor 8010, and generates a throttle pressure. The throttle pressure is supplied to the primary regulator valve 4006 via the SLT oil passage 4302. The throttle pressure is used as a pilot pressure for the primary regulator valve 4006.

  The B2 control valve 4500 selectively supplies the hydraulic pressure from one of the D range pressure oil passage 4102 and the R range pressure oil passage 4104 to the B2 brake 3620. A D range pressure oil passage 4102 and an R range pressure oil passage 4104 are connected to the B2 control valve 4500. The B2 control valve 4500 is controlled by the hydraulic pressure supplied from the SL solenoid valve (not shown) and the SLU solenoid valve (not shown) and the biasing force of the spring.

  When the SL solenoid valve is off and the SLU solenoid valve is on, the B2 control valve 4500 is in the state on the left side in FIG. In this case, the B2 brake 3620 is supplied with the hydraulic pressure adjusted from the D range pressure using the hydraulic pressure supplied from the SLU solenoid valve as a pilot pressure.

  When the SL solenoid valve is on and the SLU solenoid valve is off, the B2 control valve 4500 is in the state on the right side in FIG. In this case, the R range pressure is supplied to the B2 brake 3620.

  In the configuration of the vehicle as described above, the present invention is based on the condition that the ECU 8000 indicates the shift delay based on the state of the automatic transmission 2000 after the formation of the shift stage after the downshift is started by increasing the accelerator opening. If the condition is satisfied, the command value corresponding to the hydraulic pressure supplied to the engagement-side frictional engagement element is commanded to increase stepwise for a predetermined time Tb. When a point at which a value is output and a predetermined time Tb elapses, the command value is decreased stepwise, and the command value is increased at a predetermined rate of change using the predetermined command value as an initial value. It is characterized by a point that outputs a value. In the present embodiment, the “condition indicating the shift delay” means that the detected rotation speed of the input shaft is reduced until a predetermined time Tc elapses after the start of the shift stage. This is a condition that a state lower than the rotational speed set corresponding to the shift stage after the shift continues.

  FIG. 5 shows a functional block diagram of ECU 8000 which is a vehicle control apparatus according to the present embodiment.

  ECU 8000 includes an input interface (hereinafter referred to as an input I / F) 300, an arithmetic processing unit 400, a storage unit 500, and an output interface (hereinafter referred to as an output I / F) 600.

  The input I / F 300 includes an engine speed signal from the engine speed sensor 8020, a turbine speed signal from the input shaft speed sensor 8022, an output shaft speed signal from the output shaft speed sensor 8024, and an accelerator opening. The accelerator opening signal from the degree sensor 8010 and the throttle opening signal from the throttle opening sensor 8018 are received and transmitted to the arithmetic processing unit 400.

  The arithmetic processing unit 400 includes a shift request determination unit 402, a backlash control unit 404, a constant pressure standby control unit 406, a sweep condition determination unit 408, a surge control unit 410, a sweep control unit 412, and an end condition determination. A unit 414, an end-time control unit 416, and a release control unit 418.

  Shift request determination unit 402 determines whether there is a power-on downshift request from the driver. For example, the shift request determination unit 402 may be configured to perform a power on / down operation from the driver when a shift speed lower than the currently formed shift speed is requested in the shift map due to an increase in the accelerator opening. It is determined that there is a shift request.

  The shift diagram is, for example, a diagram corresponding to the throttle opening and the output shaft rotational speed, and an upshift line and a downshift line corresponding to each shift stage are set in advance. The shift request determination unit 402 receives the throttle opening signal received via the input I / F and the output shaft when the accelerator opening is equal to or greater than a predetermined threshold (that is, when the power is turned on). When the position specified on the shift map based on the rotational speed signal crosses the downshift line, it is determined that there is a power-on downshift request. Note that the shift request determination unit 402 may turn on the power downshift determination flag when determining that there is a power downshift request.

  When the power downshift request is determined, the backlash control unit 404 applies a clutch or a brake (hereinafter referred to as an engagement side frictional engagement element) that is brought into the engaged state from the released state when the downshift is performed. The backlash control is executed. Here, “backlash control” means that the command value for the frictional engagement element on the engagement side is increased stepwise until a predetermined time Ta elapses, and the frictional engagement element is immediately moved to immediately before the engagement. It is control to move to. For example, the backlash control unit 404 increases the command value stepwise to a predetermined value Pa (1). Note that the backlash control unit 404 may execute backlash control when the power-on downshift determination flag is turned on, for example.

  The constant pressure standby control unit 406 executes constant pressure standby control for the frictional engagement element on the engagement side after the backlash control. Here, the “constant pressure standby control” does not affect feedback control for a clutch or a brake (hereinafter referred to as a disengagement friction engagement element) that is released from an engaged state by downshifting. It is the control which waits in the state before engagement start. In the present embodiment, it is assumed that a predetermined command value Pa (2) is output to a linear solenoid corresponding to the friction element on the engagement side among SL (1) 4210 to SL (4) 4240. However, it is not particularly limited to such a control mode.

  Sweep condition determination unit 408 determines whether or not a condition indicating a shift delay (hereinafter also referred to as a sweep condition) is satisfied based on a physical quantity related to the state of automatic transmission 2000. Note that the sweep condition determination unit 406 may turn on the sweep condition determination flag when the sweep condition is satisfied, for example.

  In the present embodiment, the “physical quantity related to the state of automatic transmission 2000” is turbine rotational speed NT. Further, the “condition indicating the delay of the shift” is that the turbine rotational speed NT is set corresponding to the shift stage after the downshift until a predetermined time Tc elapses after the start of the shift stage is started. It is a condition that the state lower than the rotation speed NT (1) to be continued. The rotational speed NT (1) set corresponding to the gear position after the downshift is a rotational speed lower than the synchronous rotational speed at the gear position after the shift, and is adapted by, for example, experiments. The synchronous rotational speed at the speed stage after the shift is calculated by multiplying the output shaft speed NO detected by the output shaft speed sensor 8024 and the speed ratio at the speed stage after the speed change.

  The surge control unit 410 outputs a command value of the hydraulic pressure corresponding to the frictional engagement element on the engagement side so as to increase stepwise until a predetermined time Tb elapses, and the predetermined time Tb When elapses, a process of outputting the hydraulic pressure command value so as to decrease stepwise (hereinafter referred to as surge control) is executed.

  Specifically, when the sweep condition is satisfied, the surge control unit 410 generates a predetermined command value Pa (3) and responds to the frictional engagement element on the engagement side via the output I / F 600. Output to a linear solenoid (any one of SL (1) 4210 to SL (4) 4240). Furthermore, when a predetermined time Tb has elapsed, the surge control unit 410 generates a predetermined command value Pa (4) smaller than Pa (3) and engages via the output I / F 600. To the linear solenoid corresponding to the frictional engagement element on the side. For example, the surge control unit 410 may perform surge control when the sweep condition determination flag is on.

  The sweep control unit 412 executes processing (hereinafter referred to as sweep control) for outputting the hydraulic pressure command value corresponding to the frictional engagement element on the engagement side so as to increase at a predetermined change rate.

  Specifically, after the surge control is executed, the sweep control unit 412 is configured so that the command value increases linearly with respect to the time change at a predetermined change rate with the command value Pa (4) as an initial value. Output.

  Note that the command value Pa (4) and the predetermined rate of change may be values that are set uniformly at each gear position (that is, command values that are set uniformly for each linear solenoid). Alternatively, it may be a value set for each gear position after the shift.

  End condition determination unit 414 determines whether or not a condition that the difference in rotation speed between turbine rotation speed NT and synchronous rotation speed is within a predetermined range (hereinafter also referred to as an end condition) is satisfied. .

  Specifically, the end-time condition determination unit 414 determines the speed difference based on the turbine rotational speed signal received via the input I / F 300, the output shaft rotational speed signal, and the speed ratio at the speed stage after the shift. Is calculated. End condition determination unit 414 determines whether or not the calculated rotational speed difference is within a predetermined range, and determines that the end condition is satisfied according to the determination result.

  In the present embodiment, end-time condition determination unit 414 determines whether turbine rotational speed NT is larger than synchronous rotational speed-constant α, and turbine rotational speed NT is larger than synchronous rotational speed-constant α. If it is determined, it is determined that the end condition is satisfied. Note that the end-time condition determination unit 414 may turn on the end-time condition determination flag, for example, when it is determined that the rotational speed difference is within a predetermined range.

  When the sweep condition is satisfied (that is, when the sweep condition determination flag is ON), the end-time control unit 416 determines whether the rotation speed difference is within a predetermined range. A process of outputting a command value (hereinafter referred to as end-time control (1)) is executed so that the oil pressure is such that the frictional engagement element on the mating side is completely engaged.

  Furthermore, when the sweep condition is not satisfied (that is, when the sweep condition determination flag is OFF), the end-time control unit 416 determines that the rotational speed difference is within a predetermined range. Until the predetermined time Td elapses, the hydraulic pressure command value corresponding to the engagement-side frictional engagement element is output so as to increase stepwise. Further, when the predetermined time Td has elapsed, the end-time control unit 416 outputs the hydraulic pressure command value so as to decrease stepwise. Thereafter, the end-time control unit 416 outputs a command value so that the engagement-side frictional engagement element is fully engaged with a predetermined command value as an initial value (hereinafter referred to as end-time). Control (referred to as (2)).

  When the power downshift request is determined, the release control unit 418 controls the hydraulic pressure so that the release side frictional engagement element is released. Specifically, the release control unit 418 controls the linear solenoid corresponding to the release side frictional engagement element so that the hydraulic pressure supplied to the frictional engagement element that does not correspond to the shift stage after the shift is lowered. A signal is generated, and a control signal generated via the output I / F 600 is transmitted to the hydraulic circuit 4000.

  In the present embodiment, the shift request determination unit 402, the backlash control unit 404, the constant pressure standby control unit 406, the sweep condition determination unit 408, the surge control unit 410, the sweep control unit 412, and the end time The condition determination unit 414, the end-time control unit 416, and the release control unit 418 are all realized by a CPU (Central Processing Unit), which is the arithmetic processing unit 400, executing a program stored in the storage unit 500. However, it may be realized by hardware. Such a program is recorded on a storage medium and mounted on the vehicle.

  Various information, programs, threshold values, maps, and the like are stored in the storage unit 500, and data is read or stored from the arithmetic processing unit 400 as necessary.

  Hereinafter, with reference to FIG. 6, a control structure of a program executed by ECU 8000 which is the vehicle control apparatus according to the present embodiment will be described.

  In step (hereinafter, step is referred to as S) 100, ECU 8000 determines whether or not there is a power-on downshift request. If there is a power-on downshift request (YES in S100), the process proceeds to S102. If not (NO in S100), the process returns to S100.

  In S102, ECU 8000 starts monitoring the turbine speed and the hydraulic pressure command value. Specifically, ECU 8000 starts monitoring the turbine rotation speed NT detected by input shaft rotation speed sensor 8022 and the hydraulic pressure command value for SL (1) 4210 to SL (4) 4240 at the current gear position.

  In S104, ECU 8000 executes backlash control. In S106, ECU 8000 executes constant pressure standby control. In S108, ECU 8000 determines whether or not the sweep condition is satisfied. If the sweep condition is satisfied (YES in S108), the process proceeds to S110. If not (NO in S108), the process proceeds to S118.

  In S110, ECU 8000 executes surge control. In S112, ECU 8000 executes sweep control. In S114, ECU 8000 determines whether or not an end condition is satisfied. If the termination condition is satisfied (YES in S114), the process proceeds to S116. If not (NO in S114), the process returns to S114. In S116, ECU 8000 executes end-time control (1).

  In S118, ECU 8000 continues to perform the constant pressure standby control. In S120, ECU 8000 determines whether or not an end condition is satisfied. If the termination condition is satisfied (YES in S120), the process proceeds to S122. If not (NO in S120), the process proceeds to S108. In S122, ECU 8000 executes end-time control (2).

  The operation of ECU 8000 serving as the vehicle control apparatus according to the present embodiment based on the above-described structure and flowchart will be described with reference to FIG.

  For example, assume that automatic transmission 2000 is downshifted from the third gear to the second gear. When the C1 clutch 3640 and the B3 brake 3630 are engaged, the third gear is formed, and when the C1 clutch 3640 and the B1 brake 3610 is engaged, the second gear is formed. At the time of downshift to the second speed, the B1 brake 3610 is an engagement side frictional engagement element, and the B3 brake is a release side frictional engagement element.

  At time T (0), when the driver depresses the accelerator pedal and the accelerator opening exceeds the threshold value and the power is turned on, the power on / down from the third speed to the second speed is performed at time T (1). It is determined that there is a shift request (shift command) for shifting (YES in S100).

  At this time, monitoring of the turbine rotational speed NT and the command value of the hydraulic pressure is started (S102), and backlash control is executed for the B1 brake 3610 (S104). Therefore, ECU 8000 outputs a predetermined command value Pa (1) stepwise to SL (3) 4230, as indicated by a change (solid line) in the engagement side command value. As indicated by the change in the actual hydraulic pressure on the engagement side (broken line), the hydraulic pressure increases so as to follow the stepwise change in the command value, and the piston moves to the engagement side.

  After time T (2) after a predetermined time Ta has elapsed from the time of the speed change command at time T (1), ECU 8000 moves to the position immediately before the engagement and ends the backlash control. Then, constant pressure standby control is executed (S106). That is, ECU 8000 sets the command value for SL (3) 4230 corresponding to B1 brake 3610 to a predetermined value Pa (2) and maintains the command value.

  Further, at time T (1), ECU 8000 decreases command value Pb (1) for SL (4) 4240 corresponding to B3 brake 3630 to Pb (2) as indicated by the release-side command value (solid line). . The actual hydraulic pressure of the B3 brake 3630 decreases so as to follow the decrease in the command value as indicated by the release-side actual hydraulic pressure (broken line). Then, at time T (3), the turbine rotational speed NT starts to increase due to a decrease in the engagement force of the B3 brake 3630.

  At time T (4), when the driver stops stepping on the accelerator pedal and the power is turned off below the accelerator threshold, the engine 1000 is driven and the rate of increase in the turbine speed NT decreases. To do. Further, at time T (5), the release side command value becomes a command value indicating complete release, the release side actual hydraulic pressure also decreases with a delay in the decrease of the command value, and the B3 brake 3630 enters the fully released state.

  At time T (6) when a predetermined time Tc elapses from the time point of the shift command at time T (1), the turbine speed NT is less than the speed NT (1) set corresponding to the second gear. If so, since the sweep condition is satisfied (YES in S108), surge control is executed (S110). Therefore, the command value for SL (3) 4230 corresponding to the B1 brake 3610 is increased stepwise to a predetermined command value Pa (3) as indicated by the change (solid line) in the engagement side command value. At this time, as indicated by the change (broken line) in the engagement-side actual hydraulic pressure, the hydraulic pressure supplied to the B1 brake 3610 starts increasing so as to follow the stepwise increase in the command value.

  Sweep control is executed at time T (7) when a predetermined time Tb elapses from time T (6) (S112). That is, as indicated by a change (solid line) in the engagement-side command value, the command value is output so as to increase at a predetermined rate of change with a predetermined command value Pa (4) as an initial value. At this time, as indicated by a change (broken line) in the engagement-side actual hydraulic pressure, the hydraulic pressure increases in accordance with an increase in the engagement-side command value at a predetermined change rate. The change rate of the engagement side actual oil pressure at this time is smaller than the change rate of the engagement side actual oil pressure from time T (6) to time T (7).

  At time T (8), when the turbine rotational speed NT reaches the rotational speed NT (2) that is equal to or higher than the second-speed synchronous rotational speed-constant α, the end-time control (1) is executed (S116). As indicated by a change (solid line) in the engagement-side command value, the command value increases so that the hydraulic pressure is such that the B1 brake 3610 is completely engaged. Then, at time (9), a command value corresponding to complete engagement is output. Therefore, as indicated by the change (solid line) in the engagement-side actual hydraulic pressure, the actual hydraulic pressure increases as the command value increases, and becomes the fully engaged hydraulic pressure at time T (10).

  On the other hand, at time T (6), if the sweep condition is not satisfied (NO in S108) due to the accelerator opening being kept in the power-on state or the like (NO in S108), the constant pressure standby control is continuously executed (S118). . At this time, since the engine speed continues to rise, turbine speed NT quickly becomes equal to or greater than the value of second-speed synchronous speed-constant α, and the end condition is satisfied (YES in S120). Therefore, the end time control (2) is executed (S122). That is, until the predetermined time Td elapses, the hydraulic pressure command value corresponding to the B1 brake 3610 is output so as to increase stepwise, and when the predetermined time Td elapses, the hydraulic pressure command value is changed. After outputting so as to decrease stepwise, a command value is output so that the B1 brake 3610 is fully engaged with a predetermined command value as an initial value. Since the hydraulic pressure rises with high responsiveness by surge control, the hydraulic pressure quickly rises to the fully engaged hydraulic pressure, and the shift is completed.

  Hereinafter, referring to FIG. 8, when the sweep condition is satisfied, the turbine speed and the engagement side when the surge control is performed at the time of the end control without performing the surge control before the sweep control. Changes in the command value, the engagement side actual hydraulic pressure, the release side command value, the release side actual hydraulic pressure, and the accelerator opening will be described. It should be noted that until time T (6), the same change as in FIG. 7 is shown, and the detailed description thereof will not be repeated.

  As shown in FIG. 8, at time T (6), if the turbine rotational speed NT is equal to or lower than the rotational speed NT (1) set corresponding to the second gear, the sweep condition is satisfied, so that the sweep control is performed. Executed. Therefore, as indicated by a change (solid line) in the engagement-side command value, a command value for SL (3) 4230 corresponding to the B1 brake 3610 is determined in advance with a predetermined command value Pa ′ (3) as an initial value. The command value is output so as to increase at the specified change rate. At this time, as shown by the change in the actual engagement side hydraulic pressure (broken line), the increase in the engagement side command value at the predetermined change rate is gradually increased to the predetermined change rate. Hydraulic pressure increases. Therefore, the actual oil pressure from time T (6) to time T ′ (7) in FIG. 8 is compared with the response of the actual oil pressure during the sweep control from time T (7) to time T (8) in FIG. There is a delay in the response.

  In addition, after the engine 1000 is in a driven state and the response of the actual hydraulic pressure on the engagement side is delayed, the turbine speed NT decreases after the time T (6) to the time T ′ (7). It increases as the engagement side actual hydraulic pressure rises.

  At time T ′ (7), when the turbine speed NT becomes equal to or greater than the second speed synchronous speed-constant α, the surge control is executed. Therefore, as indicated by a change (solid line) in the engagement-side command value, the command value Pa ′ determined in advance until a command time for the SL (3) 4230 corresponding to the B1 brake 3610 elapses. It is raised step by step to (4). At this time, as indicated by the change (broken line) in the engagement-side actual hydraulic pressure, the hydraulic pressure supplied to the B1 brake 3610 starts increasing so as to follow the stepwise increase in the command value.

  However, the actual hydraulic pressure on the engagement side suddenly increases (hydraulic pressure boost) due to the stepwise increase in the command value due to surge control. Therefore, the engagement of the B1 brake 3610 proceeds rapidly, and the turbine rotational speed NT rapidly approaches the second-speed synchronous rotational speed. At this time, a shock may occur in the automatic transmission due to a sudden change in the turbine speed NT.

  Therefore, when the sweep condition is satisfied, the actual hydraulic pressure can be increased with high responsiveness to the command value of the engagement side frictional engagement element during the sweep control by performing the surge control before the sweep control. Therefore, the increase in turbine rotation speed is promoted. Therefore, the shift time can be shortened when the sweep condition is satisfied. Furthermore, since the surge control is not performed during the end-time control, the occurrence of a shock is suppressed by suppressing a rapid increase in the actual pressure.

  As described above, according to the vehicle control apparatus of the present embodiment, surge control is executed when the sweep condition is satisfied during the power-on downshift. Thereby, when the condition is satisfied, the actual hydraulic pressure of the frictional engagement element on the engagement side can be quickly increased as compared with the case where the sweep control is executed. In addition, when the sweep condition is satisfied, the command value is increased stepwise and decreased after the elapse of a predetermined time, so that the occurrence of shift shock due to excessive application of hydraulic pressure on the engagement side during shift is suppressed. can do. Further, since the sweep control is performed after the surge control, the downshift can be progressed gradually. Therefore, it is possible to suppress shift time delay and shift shock. Therefore, it is possible to provide a vehicle control device and a control method that suppress a shift time delay caused by a response delay of hydraulic pressure when the synchronous rotational speed is not reached during a power-on downshift.

  Further, until a predetermined time Tc elapses after the start of the formation of the shift speed, the detected rotation speed of the input shaft is the rotation speed NT (1) set corresponding to the shift speed after the downshift. If the state lower than is continued, it can be determined that the progress of the shift is delayed. For this reason, when the condition is satisfied, the command value is increased stepwise, so that the shift time delay can be suppressed while the shift shock and the hydraulic response delay are suppressed.

  Further, when the condition is satisfied, the engagement side hydraulic pressure is increased due to the stepwise change of the command value. Therefore, when the rotational speed difference from the synchronous rotational speed is within a predetermined range (that is, the turbine rotational speed is equal to or higher than the synchronous rotational speed-constant α), the hydraulic pressure at which the second friction engagement element is fully engaged is obtained. By outputting the command value so as to increase up to, it is possible to shift while suppressing the occurrence of shift shock caused by excessive application of hydraulic pressure on the engagement side.

  When the condition is not satisfied, the stepwise change in the command value and the increase at the predetermined change rate are not performed, so that the hydraulic pressure on the engagement side is relatively low. Therefore, when the rotational speed difference from the synchronous rotational speed is within a predetermined range, the hydraulic pressure can be increased with high responsiveness by changing the command value stepwise. As a result, it is possible to quickly form the shift stage after the downshift.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a schematic block diagram which shows the power train controlled by ECU which is the control apparatus of the vehicle which concerns on this Embodiment. It is a skeleton figure which shows the gear train in an automatic transmission. It is a figure which shows the operation | movement table | surface of the automatic transmission 2000. FIG. It is a figure which shows the principal part of the hydraulic circuit in an automatic transmission. It is a functional block diagram of ECU which is a control device of vehicles concerning this embodiment. It is a flowchart which shows the control structure of the program performed with ECU which is the control apparatus of the vehicle which concerns on this Embodiment. It is a timing chart which shows operation | movement of ECU which is a control apparatus of the vehicle which concerns on this Embodiment. It is a timing chart which shows change of oil pressure when surge control is not carried out before sweep control.

Explanation of symbols

  300 input I / F, 400 arithmetic processing unit, 402 shift request determination unit, 404 backlash control unit, 406 constant pressure standby control unit, 408 sweep condition determination unit, 410 surge control unit, 412 sweep control unit, 414 end condition determination , 416 end control unit, 418 release control unit, 500 storage unit, 600 output I / F, 1000 engine, 2000 automatic transmission, 3000 planetary gear unit, 3100 input shaft, 3200 torque converter, 3210 output shaft, 3610 B1 brake, 3620 B2 brake, 3630 B3 brake, 3640 C1 clutch, 3650 C2 clutch, 3660 One-way clutch F, 4000 Hydraulic circuit, 4004 Oil pump, 4006 Primary regulator valve 4100 Manual valve, 4200 solenoid modulator valve, 4210 SL1 linear solenoid, 4220 SL2 linear solenoid, 4230 SL3 linear solenoid, 4240 SL4 linear solenoid, 4300 SLT linear solenoid, 4500 B2 control valve, 5000 differential gear, 6000 drive shaft, 7000 front wheel, 8000 ECU, 8002 vehicle speed sensor, 8004 shift lever, 8006 position switch, 8008 accelerator pedal, 8010 accelerator opening sensor, 8012 brake pedal, 8014 stroke sensor, 8016 electronic throttle valve, 8018 throttle opening sensor, 8020 engine speed sensor, 8022 input shaft rotational speed sensor, 024 Output shaft speed sensor.

Claims (6)

The released first frictional engagement element is engaged by the hydraulic pressure supplied based on the command value output to the hydraulic circuit, and the second frictional engagement element in the engaged state is released to reduce A control device for a vehicle equipped with an automatic transmission that forms a shift stage after shifting,
Detecting means for detecting a physical quantity related to the state of the automatic transmission;
Determining means for determining whether a condition indicating a shift delay is established based on a state of the automatic transmission after the formation of the shift stage after the downshift is started due to an increase in the accelerator opening; ,
When the condition is satisfied, the command value corresponding to the hydraulic pressure supplied to the first friction engagement element is increased stepwise by a predetermined time, and when the predetermined time has elapsed, the command value Means for outputting in a stepwise manner,
Look including a means for outputting a command value to increase the predetermined command value at a predetermined rate of change as an initial value,
The detection means includes means for detecting the rotational speed of the input shaft of the automatic transmission,
The controller is
Means for calculating a rotational speed difference between the detected rotational speed and the synchronous rotational speed after downshift;
When the condition is not satisfied and the detected rotational speed difference falls within a predetermined range, a command value corresponding to the engagement hydraulic pressure of the first friction engagement element is determined for a predetermined time. Means for outputting the command value so as to decrease stepwise after being increased stepwise only,
The vehicle control apparatus further includes means for outputting a command value so as to increase until a hydraulic pressure at which the first friction engagement element is fully engaged is set with a predetermined command value as an initial value . Before SL controller if the previous SL condition is satisfied, at a range of the calculated rotational speed difference is a predetermined increase to said first frictional engagement element is a hydraulic completely engaged further comprising a hand stage for outputting a command value as the control apparatus for a vehicle according to claim 1. The condition is that the detected rotational speed of the input shaft is set corresponding to the speed stage after downshifting until a predetermined time has elapsed since the start of the speed stage. The vehicle control device according to claim 1 , wherein the vehicle is in a condition that a lower state continues. The released first frictional engagement element is engaged by the hydraulic pressure supplied based on the command value output to the hydraulic circuit, and the second frictional engagement element in the engaged state is released to reduce A method for controlling a vehicle equipped with an automatic transmission that forms a shift stage after shifting,
A detecting step for detecting a physical quantity related to the state of the automatic transmission;
A step of determining whether or not a predetermined condition indicating a shift delay is satisfied based on a state of the automatic transmission after the formation of the shift stage after the downshift is started due to an increase in the accelerator opening; When,
When the condition is satisfied, the command value corresponding to the hydraulic pressure supplied to the first friction engagement element is increased stepwise by a predetermined time, and when the predetermined time has elapsed, the command value Outputting in a stepwise manner,
See containing and outputting a predetermined command value and the command value to increase at a predetermined rate of change as an initial value,
The detecting step includes a step of detecting the rotational speed of the input shaft of the automatic transmission,
The control method is:
Calculating a rotational speed difference between the detected rotational speed and the synchronous rotational speed after downshift;
When the condition is not satisfied and the calculated rotational speed difference is within a predetermined range, a command value corresponding to the engagement hydraulic pressure of the first friction engagement element is determined for a predetermined time. A step of outputting a command value so as to decrease stepwise after being increased stepwise only,
And a step of outputting a command value so as to increase until a hydraulic pressure at which the first friction engagement element is completely engaged is set using a predetermined command value as an initial value . Increased until SL control method, if the previous SL condition is satisfied, at a range of the calculated rotational speed difference is the predetermined, the oil pressure of the first frictional engagement element is fully engaged steps including for outputting a command value to the control method for a vehicle according to claim 4. The predetermined condition is that the rotation speed of the detected input shaft corresponds to the gear position after downshifting until a predetermined time has elapsed since the formation of the gear speed is started. The vehicle control method according to claim 4, wherein the vehicle is in a condition that a lower state continues.

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